plugin: add crosvm_net_get_config

BUG=none
TEST=sudo cargo test --features plugin

Change-Id: Ib38fad250295d73529dff0451345b4274a261073
Reviewed-on: https://chromium-review.googlesource.com/911943
Commit-Ready: Stephen Barber <smbarber@chromium.org>
Tested-by: Stephen Barber <smbarber@chromium.org>
Reviewed-by: Zach Reizner <zachr@chromium.org>

3 files changed, 98 insertions, 0 deletions

diff --git a/tests/plugin.policy b/tests/plugin.policy
index 960c8e5..773ea24 100644
--- a/tests/plugin.policy
+++ b/tests/plugin.policy
@@ -33,6 +33,8 @@ fstat: 1
 ftruncate: 1
 getcwd: 1
 getrlimit: 1
+# TUNGETFEATURES
+ioctl: arg1 == 0x800454CF
 madvise: 1
 memfd_create: 1
 mmap: 1
diff --git a/tests/plugin_net_config.c b/tests/plugin_net_config.c
new file mode 100644
index 0000000..f11fa10
--- /dev/null
+++ b/tests/plugin_net_config.c
@@ -0,0 +1,85 @@
+/*
+ * Copyright 2018 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include <arpa/inet.h>
+#include <linux/if_tun.h>
+#include <sys/ioctl.h>
+
+#include <errno.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "crosvm.h"
+
+/*
+ * These must match the network arguments supplied to the plugin in plugins.rs.
+ * IPv4 addresses here are in host-native byte order.
+ */
+const uint32_t expected_ip = 0x64735c05; // 100.115.92.5
+const uint32_t expected_netmask = 0xfffffffc; // 255.255.255.252
+const uint8_t expected_mac[] = {0xde, 0x21, 0xe8, 0x47, 0x6b, 0x6a};
+
+int main(int argc, char** argv) {
+    struct crosvm *crosvm;
+    struct crosvm_net_config net_config;
+    int ret = crosvm_connect(&crosvm);
+
+    if (ret) {
+        fprintf(stderr, "failed to connect to crosvm: %d\n", ret);
+        return 1;
+    }
+
+    ret = crosvm_net_get_config(crosvm, &net_config);
+    if (ret) {
+        fprintf(stderr, "failed to get crosvm net config: %d\n", ret);
+        return 1;
+    }
+
+    if (net_config.tap_fd < 0) {
+        fprintf(stderr, "fd %d is < 0\n", net_config.tap_fd);
+        return 1;
+    }
+
+    unsigned int features;
+    if (ioctl(net_config.tap_fd, TUNGETFEATURES, &features) < 0) {
+        fprintf(stderr,
+                "failed to read tap features: %s\n",
+                strerror(errno));
+        return 1;
+    }
+
+    if (net_config.host_ip != htonl(expected_ip)) {
+        char ip_addr[INET_ADDRSTRLEN];
+        inet_ntop(AF_INET, &net_config.host_ip, ip_addr, sizeof(ip_addr));
+        fprintf(stderr, "ip %s != 100.115.92.5\n", ip_addr);
+        return 1;
+    }
+
+    if (net_config.netmask != htonl(expected_netmask)) {
+        char netmask[INET_ADDRSTRLEN];
+        inet_ntop(AF_INET, &net_config.netmask, netmask, sizeof(netmask));
+        fprintf(stderr, "netmask %s != 255.255.255.252\n", netmask);
+        return 1;
+    }
+
+    if (memcmp(net_config.host_mac_address,
+               expected_mac,
+               sizeof(expected_mac)) != 0) {
+        fprintf(stderr,
+                "mac %02X:%02X:%02X:%02X:%02X:%02X != de:21:e8:47:6b:6a\n",
+                net_config.host_mac_address[0],
+                net_config.host_mac_address[1],
+                net_config.host_mac_address[2],
+                net_config.host_mac_address[3],
+                net_config.host_mac_address[4],
+                net_config.host_mac_address[5]);
+        return 1;
+    }
+
+    return 0;
+}
diff --git a/tests/plugins.rs b/tests/plugins.rs
index d036e97..e858c9a 100644
--- a/tests/plugins.rs
+++ b/tests/plugins.rs
@@ -83,6 +83,12 @@ fn run_plugin(bin_path: &Path, with_sandbox: bool) {
     cmd.args(&["run",
                 "-c",
                 "1",
+                "--host_ip",
+                "100.115.92.5",
+                "--netmask",
+                "255.255.255.252",
+                "--mac",
+                "de:21:e8:47:6b:6a",
                 "--seccomp-policy-dir",
                 "tests",
                 "--plugin"])
@@ -241,6 +247,11 @@ fn test_vcpu_pause() {
 }
 
 #[test]
+fn test_net_config() {
+    test_plugin(include_str!("plugin_net_config.c"));
+}
+
+#[test]
 fn test_debugregs() {
     let mini_plugin = MiniPlugin {
         assembly_src: "org 0x1000